hashmapdemo.java

JAVA的一些基础教程

import java.util.Set;                                         
import java.util.Map;                                         
import java.util.HashMap;                                     
import java.util.Iterator;                                    
                                                              
public class HashMapDemo                                      
{                                                             
    public static void main( String[] args )                  
    {                                                         
         Map map = new HashMap();                             
                                                              
         map.put( new Integer( 1 ), "One" );                  
         map.put( new Integer( 2 ), "Two" );                  
         map.put( new Integer( 3 ), "Three" );                
         map.put( new Integer( 4 ), "Four" );                 
         map.put( new Integer( 5 ), "Five" );                 
         map.put( new Integer( 6 ), "Six" );                  
         map.put( new Integer( 7 ), "Seven" );                
         map.put( new Integer( 8 ), "Eight" );                
         map.put( new Integer( 9 ), "Nine" );                 
         map.put( new Integer( 10 ), "Ten" );                 
                                                              
         System.out.println( "Map Values Before: " );         
         Set keys = map.keySet();                             
         for( Iterator i=keys.iterator(); i.hasNext(); )      
         {                                                    
             Integer key = ( Integer )i.next();               
             String value = ( String )map.get( key );         
             System.out.print( key + " = " + value +"\t");    
         }                                                    
                                                              
         System.out.println( "\nRemove element with key 6" ); 
         map.remove( new Integer( 6 ) );                      
                                                              
         System.out.println( "\nMap Values After: " );        
         keys = map.keySet();                                 
         for( Iterator i=keys.iterator(); i.hasNext(); )      
         {                                                    
             Integer key = ( Integer )i.next();               
             String value = ( String )map.get( key );         
             System.out.print( key + " = " + value +"\t");    
         }                                                    
     }                                                        
 }